Shuttle.



G. HOFFMANN.

SHUTTLE.

APPLICATION FILED JULY 13, 1911.

1,035,792, I Patented Aug. 13,1912.

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GOTTFRIED HOFFMANN, OF COLLEGE POINT, NEW YORK.

SHUTTLE.

Specification of Letters Patent.

Patented Aug. 1 3,1912.

Application filed July 13, 1911. Serial No. 638,236.

To all whom it may concern Be it known that I, Go'r'rruino Horr- MANN, a citizen of the United States of America, residing at College Point, Long Island, in the county of Queens and State of New York, have invented certain new and useful Improvements in Shuttles, of which the following is a specification.

The present invention relates to shuttles, particularly for silk looms. Owing to the thinness of the silk weft thread, the latter is liable to easily tear. To avoid this, the bobbins in such shuttles must be so arranged as to be capable of freely revolving without the slightest resistance. However, during the operation of the shuttle there are certain periods at which a retardation of the rotary motion of the bobbin is required, namely, then when the shuttle at the ends of its stroke is shifted to a parallel line. At such periods, the unwinding of the thread is not required, and if the bobbin is then permitted to continue its rotation with the usual speed, the unwound thread curls around the bobbin, becoming entangled or forming loops. Many attempts have been made to prevent such curling of the thread, but without success.

The object of my invention is to overcome the above named drawbacks with the simplest possible means that could be applied to old shuttles just as easily as to new ones, without requiring any change in the construction thereof.

My invention will be easily understood by reference to the accompanying drawing, in which similar reference letters denote corresponding parts and in which- Figure 1 is a side elevation of a shuttle and Fig. 2 is a cross section on line 2-2 of Fig. 1.

In the drawing, a denotes a shuttle of the ordinary construction used for silk looms, and b the bobbin carrying the silk weft thread 0. The bobbin is loosely borne on a pin (Z fixed in the shuttle in the usual manner. Ordinarily the thread unwinding from the bobbin is conveyed through eyelets e, 6' attached to springs f, f and outward through an eyelet g. The bobbin being caused to revolve on its pin by the draft exerted on the thread during the weaving operation of the shuttle, will continue its rotary motion by its own inertia when the draft has ceased, as for instance, at the ends of the stroke of the shuttle when it is shifted transversely to a parallel line. In consequence of this continued rotation, the thread curls around the bobbin becoming entangled or forming loops or knots. To avoid this, it is necessary to provide such means which at the moment when the draft on the thread ceases will automatically brake the bobbin thereby retarding its rotation or arresting it, and which as soon as the draft commences will release the bobbin allowing it to revolve again with the usual speed. To accomplish this object, I provide a substantially rigid U-shaped arm h, one end of which is formed with a pin 2' that pivotally engages a socket fixed to the shuttle above one end of the pin (Z. This arm when free will project vertically downward (see dotted lines in Fig. 1) without touching the end of the bobbin and thus not interfere with the motion thereof. The lower portion h of said arm is somewhat curved and is extended below the bobbin. To the how it of the U-shaped arm is fastened a string is or the like, the other end of which is fixed to an eyelet e which together with the eyelet e is secured to the spring f. Said spring has the tension to bring the two members of the U-shaped arm in frictional contact with one of the end surfaces b of the bobbin 2) thereby braking its rotary movement.

In addition to the eyelet e, e, e and g, I provide an eyelet Z and convey the end of the thread 0 from the bobbin downward through the eyelet Z, then upward through the eyelet e, transversely to and through the eyelet e, transversely backward to and through the eyelet e and finally downward and outward through the eyelet g.

lVhen a draft is exerted on the thread 0, the latter will draw the eyelets e, e toward the arm it against the tension of their spring f" and permitting the arm to adopt its normal vertical position, in which it will be out of contact with the bobbin, so that the latter will be released and permitted to be revolved unrestrained by the draft of the thread. As soon, however, as the draft ceases, the spring f contracts and draws the eyelets e, a backward and the string is taut, bringing the arm again in frictional contact with the bobbin.

To increase the friction or the braking effect of the arm on the bobbin, I found it advantageous to flatten and sharpen the members of the U-shaped arm at the points where they are to frictionally engage the bobbin as at m. The result accomplished by this construction is that the Weft thread 0 at no time will be allowed to slacken and thereby become curled around the bobbin, so that the liability of its tearing isgreatly reduced.

Since various modifications in the construction may be designed, without departing from the spirit of my invention, I do not Wish to restrict myself to the particular construction shown and described.

W hat I claim and desire to secure by Letters Patent is:

1. In a shuttle, the combination with a bobbin of a pivotally suspended braking member arranged opposite one end of the bobbin and adapted normally to be out of contact with the latter and resilient means through which the weft thread is passed, and means connecting said member to one of said resilient means, so that when the draft on the thread ceases, it will be caused to'frictionally engage the said bobbin and brake its rotary motion.

2. In a shuttle, the combination with a bobbin, of a pivotally suspended braking member arranged opposite one end of the bobbin and adapted to normally be out of contact with the latter, spring actuated guide members and stationary guide members for the weft thread, and means connecting said braking member to one of said spring guide members, the weft thread being so guided through said guide members that when the draft ceases, it will be caused to frictionally engage the bobbin and brake its rotary motion.

3. In a shuttle having an eyelet through which the weft thread passes out, the combination with a bobbin, of spring actuated guide members for the Weft thread, a stationary guide member therefor near said eyelet, a hook-shaped braking member pivotally suspended opposite one end of said bobbin and adapted to normally be out of contact with the latter, a flexible means connecting said braking member to one of said spring guide members, the weft thread passing from the bobbin through the said spring actuated members, through the stationary guide member and out through the eyelet in the shuttle in such a manner that when the draft on the weft thread ceases, the braking member will be caused to frictionally engage the opposite end. of the bobbin and brake its rotary motion.

In testimony whereof I aHiX my signature in presence of two Witnesses.

eorrrmnn HOFFMANN.

Vitnesses ELLIs V. LEVY, MAX D. ORDMANN.

Copies ofthis'patentmay beobtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

